I'm reproducing portions of my Spokesman-Review, Handle Extra story for those outside the paper's circulation area. This version is slightly different due lack of editing.
An error, quoting Chip Corsi, Region 1 F&G Supervisor, saying the following is incorrect. the quote was confused with another: Chip points out correctly, that Bull trout and Cutthroat trout would have gone that far upriver, but not kokanee.
First the Cabinet Gorge Dam in Montana, chopped off the river seven miles upstream. Removing the 75 or 80 miles of upriver spawning habitat.
Lake Pend Oreille is dying. It isn’t dying from toxic waste or pollution, but is dying economically. This pristine body of water, once the home of commercial fishing, is in a slump that many experts are afraid may be irreversible. The death of this lake was caused by human interruption of the food chain. Re-intervention to try to right the wrongs of the past are in motion, but hold only small hope for recovery. In this, the first of two parts, we are going to visit the causes. Part two will address what is being done to mitigate and thirdly, the results as projected. We will as well, talk to business owners around the lake regarding the economic effect of this crisis.
Many years ago, in 1925, Macinaw, a long lived char or Lake Trout,” were planted in Lake Pend Oreille and priest Lake by the then, “U.S. Fish Commission,” later reformed as the U.S. Fish and Wildlife Commission. Land locked Sockeye Salmon, locally referred to as kokanee, Blueback or Silvers, were flushed down the Clark Fork River, from Flathead Lake in Montana during the regular spring floods of the day. In 1941, Idaho Fish & Game, brought both Gerrard Rainbow Trout, and later, in the sixties, Mysis shrimp from Kootenai Lake in British Columbia, to Lake Pend Oreille.
The apparent thinking at the time, was Idaho needed trout capable of attaining record size. It was also felt that since Mysis Shrimp were present in Kootenai Lake, and was a feed source for the kokanee, that they would be an additional value. The problem though, was that shrimp feed on the surface of the water at night, and go deep during daylight hours. In Kootenai Lake, the West Arm being fairly shallow, this caused no problems. In Lake Pend Oreille it did. kokanee couldn’t reach the shrimp at the depths they sank to in Lake Pend Oreille because of the 1150 foot depth of the lake. In Lake Pend Oreille, the shrimp dive down 400 to 600 feet deep during daylight hours.
What the addition of Mysis Shrimp did do however, is create a huge food source for the deep living Macinaw, and also Whitefish, the largest species in terms of numbers in the lake. creating an explosion in their juvenile population. Macinaw, can live up to twenty years old,or longer, and Gerrard Trout, seven to ten. Both, when attaining a size of about sixteen inches, start feeding on smaller fish. Prior to that they are basically insect eaters. The ideal size from the Macinaw perspective, is the one to two year old kokanee fry. The larger the predator grows, the larger fish they consume.
After introduction in the Forties, both kokanee and Rainbow Trout flourished in a sustainable pattern. The World Record Gerrard Rainbow was caught in 1947, by Wes Hamlet. During World War Two, hardly any fishing went on. In 1945-46 and after, the untouched fishery produced huge numbers of kokanee and the record Rainbow Trout of 37 pounds. At one time, kokanee were fished commercially. Many old timers remember their Fathers hand lining with jigs, for wash tubs full of 12 to 15 inch kokanee. Commercial fishing was finally closed in 1973. The Old smoke house still stands sentinel at the south end of the Long Bridge in Sandpoint, but long since stopped the major business of smoking kokanee.
While this was going on, the Mysis Shrimp were quietly reproducing at phenomenal rates, without, seemingly any natural enemies, at least those that could reach them. All was still well until 1952. This was the year that two very significant dams were built. Cabinet Gorge, on the Clark Fork River in Montana and Albeni Falls on the Pend Oreille River at Priest River, Idaho. These two dams were to the Lake Pend Oreille fishery, the death knell, but for different reasons.
First the Cabinet Gorge Dam in Montana, chopped off the river seven miles upstream. Removing the 75 or 80 miles of upriver spawning habitat. After the Clark Fork ceased to be of use, only the strain of kokanee that had adapted to spawning in the lake shore gravels were left. kokanee spawn in the late fall, usually late November and early December. Granite Creek, on the east side of Lake Pend Oreille and a few very small creeks were left, mostly too steep for fish to swim up. Albeni Falls was the final nail in their coffin. During the 1960's, the Bonneville Power Administration managed to convince the U.S. Army Corps of Engineers, controllers of the dam, to radically lower the lake level, producing more flow for the Columbia River system and subsequently more Winter power generation.
That did it. kokanee, the key food fish for larger fish began to disappear rapidly. They did this because in the beginning, Albeni Dam lowered the lake level, after the kokanee had spawned, thereby leaving redds or egg nests high and dry. Even then, everyone was still in denial. This practice continued until finally, in 1996, IDFG and the Corps of Engineers reached agreement to lower the lake prior to the kokanee spawn. Fish & Game Department closed fishing for kokanee altogether in 2000. Avista ponied up large amounts of cash for mitigation, but it began to look like to little, too late. One such result of mitigation, was that Idaho Fish & Game opened an office in Bayview, nestled at the south end of the lake. The purpose of this office was to establish an unprecedented massive effort to recover the kokanee population.
It needs to be explained that kokanee are a Salmon that spawns every fourth year, then dies. Using Buck Rogers like equipment, Fish & Game cris-cross the lake all Summer long using hydro-acoustic sonar. This equipment can type, size and count the fish as it passes over them. Based on these counts, here are the numbers for 2007, keeping in mind that predation accounts for the first and second year.
Fry 1-2" 3.8 million
1st year 2.2 million
2nd year 72,400
3rd year 18,108
4th year, a statistical zero, with only a scattered few spawners located. ...
More to follow the publishing of part two in next Saturday's Handle Extra.
Parting Shot -- 2.21.17
10 hours ago